Hemicellulosic moieties from opium poppy and cotton stalks were solublized in water at varying alkali concentrations (NaOH) and peroxide (H 2 O 2 ). The hemicelluloses were then be precipitated from the solutions by acidification. The 2.0 and 3.0% H 2 O 2 extractions resulted in a yield of 0.8 and 0.71%, respectively, accounting for 3.2 and 2.9% of the hemicelluloses present in the opium poppy stalks. A similar result was also obtained for cotton stalks. It was found that alkaline peroxide is an effective agent for solubilization of hemicelluloses from opium poppy and cotton stalks.